Have just found a new online introduction to R, Quick-R, which looks terrific. I have stacks of print-outs of R documentation littering the apartment, but there's something demoralising about leafing through a PDF - not least because, with the passage of time, the most frequently consulted pages tend to go missing. (I'm constantly coming across stray pages of R documentation while looking for keys, credit card, gym card, passport...) I do also have a couple of books, whose pages don't go missing - but if one wants to use any code one either has to type it out by hand or go to the relevant website. So Robert I. Kabacoff has done all beginners and improvers a big favour.
Thanks to Kabakoff I learn that Deepayan Sarkar's Lattice, Multivariate Data Visualization with R has just been published by Springer. Also great news.